Volvo: 1986 240DL Pooooor performance, willow tree, graffitied

Question
My 1986 240 DL will not accelerate !!
The engine BOGS down with a deep moan when accelerating.  I replaced the main fuel pump and canister filter as well as the O2 sensor.  The car seemed normal again, responsive, shifting and down shifting as demands changed, Highway speed maintainable at cruse. After 150 miles of highway driving, symtoms began again, BOG goes the engine, lack of power to the point of embarrassment.  With "Car in Tow" graffitied on the back window and 150 mile pull down the Jersey turnpike to her favorite repair shop, she is again asking for my tender touch and repair.
I can make the engine BOG with a manual twist of the throttle and watch the engine shake like a willow tree at 3/4 to full throttle.

I am at a loss, is this a common problem with these vehicles?  Milage is over 250,000. All systems seem to be normal, what should the Doctor be looking for?

Mike  

Answer
Hello Michael! There could be a problem with the MAF sensor or fuel presure regulator. That would be the most common cause. There can be other reasons for that problem, but I would start there. If you are not familiar with how to check these items, it is best to let a qualified Volvo technician do it for you. I hopr this info helps. I'll be here if you need more help.

Jimmy